“Profitability of nontoxic endophyte-infected tall fescue-based stocker programs was, at a minimum, three times greater than toxic endophyte-infected tall fescue-based stocker programs in any scenario.” That’s the conclusion of a four-year study – “Impact of Clover Additions to Toxic or Nontoxic Endophyte-Infected Tall Fescue on Animal Performance and Economics of Stocker Programs” – conducted by researchers at the University of Arkansas (UA) and the Samuel Roberts Noble Foundation at Ardmore, OK.

According to UA researchers, in that university’s monthly beef research update, steers grazing nontoxic endophyte-infected tall fescue gained 0.46 lb./day more in the autumn and 1.26 lbs./day more in the spring, than steers grazing toxic endophyte-infected tall fescue. The study compared toxic endophyte-infected tall fescue with the nontoxic endophyte-infected tall fescue cultivars Jesup MaxQ and Texoma MaxQII, either with nitrogen applied in autumn and spring or grown in combination with white clover. Autumn pastures were stocked at 1.64 steers/acre. Initial stocking rates were adjusted to match forage mass in the spring. Enterprise budgeting was used to compute net returns.

According to UA researchers:

  • Clovers did not affect average daily gain in the autumn but increased average daily gain in the spring by 0.44 lbs/day; stocking rates and grazing days per acre were decreased with clovers regardless of season.
  • Interseeding clovers into toxic endophyte-infected tall fescue pastures had no effect on body weight gain per acre.
  • Body weight gain per acre for nontoxic endophyte-infected tall fescue was 79% greater than toxic endophyte-infected tall fescue. Nontoxic endophyte-infected tall fescue with nitrogen produced 17% more body weight gain per acre than clover.
  • Neither nitrogen nor clover affected body weight gain per acre of toxic endophyte-infected tall fescue pastures.
  • Although clover pastures were not as productive, net returns were increased because of reduced costs of production.
  • Using clover resulted in similar improvements in average daily gain for both toxic endophyte-infected and nontoxic endophyte-infected tall fescue pastures.